1. Field of the Invention
The present inventive concept relates to a method of fabricating a semiconductor device, and more particularly, to a method of fabricating a complementary metal oxide semiconductor (CMOS).
2. Description of the Related Art
Recently, metal gates have been frequently used instead of polysilicon gates to improve device characteristics. Metal gates can be fabricated using a replacement metal gate process. Meanwhile, a complementary metal oxide semiconductor (CMOS) should be fabricated such that a p-channel metal oxide semiconductor (PMOS) and an n-channel metal oxide semiconductor (NMOS) have different work functions. To this end, however, a plurality of films need to be deposited in a trench during the replacement metal gate process.